Double thickness wall construction for rockets



April 7, 1964 J. w. TUMAVICUS 3,127,667

DOUBLE THICKNESS WALL CONSTRUCTION FOR ROCKETS Filed June 23, 1959 F'ICLB FIG 4 INVENTOR JULIUS W- TUMAVICLJS BY mm ATTORNEY United States Patent Ofiice 3,127,667. Patented Apr. 7, 1964 3,127,667 DOUBLE THICKNESS WALL CONSTRUCTION FOR ROCKETS Julius W. Tumavicus, Old Saybrook, Conn, assignor to United Aircraft Corporation, East Hartford, Conn, a

corporation of Delaware Filed June 23, 1959, Ser. No. 822,332 2 Claims. (Cl. 29-157) This invention relates to a double wall construction for a rocket, particularly for a wall of a combustion chamber or nozzle.

One feature of the invention is the support of the inner and outer walls in a double wall construction in concentrio relation to each other by a number of substantially radially extending elements secured to both walls. Another feature is the use of bendable supporting elements between the walls to accommodate the small relative axial movement between the walls resulting from thermal changes during operation.

One feature of the invention is a method for producing a double wall structure of this type by inserting the spacer elements radially through the two walls and then brazing them in place. Another feature is the weaving of a wire across the space between the Walls and through the walls to form the connecting elements and then brazing the wire in position.

Other features and advantages will be apparent from the specification and claims, and from the accompanying drawing which illustrates an embodiment of the invention.

FIG. 1 is a sectional view through a double-walled nozzle.

FIG. 2 is an enlarged sectional view through a portion of the double wall showing a step in the manufacture of the wall.

FIG. 3 is a fragmentary sectional view substantially along the line 33 of FIG. 2.

FIG. 4 is a sectional view on an enlarged scale of a portion of the wall structure of FIG. 1.

Referring first to FIG. 1, the invention is shown in a wall construction for a rocket including a combustion chamber 2, a nozzle throat 4 and a diverging nozzle discharge 6. The wall 8 which forms the rocket consists of inner and outer wall elements 10 and 12, respectively, which are arranged in concentric spaced relation.

The inner and outer walls are held in the desired spaced relation by radially extending connecting elements 14, the ends of which are positioned in aligned openings 16 and 17 in the inner and outer walls, respectively. These elements are brazed within the openings 16 and 17 so that the connecting elements are securely retained in position. The spaced elements 14 are preferably relatively thin and, accordingly, bendable to some extent in order that there may be a slight relative axial movement between the inner and outer walls as the former is heated more rapidly than the latter during the operation of the rocket.

It will be apparent from FIGS. 1 and 2 that each element 14 is preferably in a radial plane when viewed in an axial direction. Each of these elements is preferably arranged so that it extends at right angles to both inner and outer walls. Accordingly, where the rocket wall is cylindrical, the element 14 extends radially when viewed either in a transverse plane or in a longitudinal plane. Where the walls converge or diverge, however, the elements 14 are radial when viewed in a transverse plane so that these elements may be said to be radial. When viewed in a longitudinal plane, however, the elements have a longitudinal component, as clearly shown in FIG. 1.

Although the elements 14 may be formed as separate pieces of the appropriate length to be inserted into the position shown in FIG. 4 and then brazed in place, it may be desirable for ease of assembly to utilize a wire 18 which may be woven inwardly and outwardly through adjacent sets of holes 16 and 17 in the wall elements 10 and 12 so that the portions of the wire overlying either of the inner or outer wall elements will retain in position the radially extending portions of the wire until these portions can be brazed to the wall elements.

This arrangement for weaving the wire in and out to produce the spacer elements results in circumferentially or axially extending portions 20 and 22 of the wire which do not leave smooth inner and outer wall surfaces. Accordingly, if the roughness caused by these portions 20 and 22 resting on the wall surfaces is objectionable, these portions of the wire, after the brazing operation is completed, may be removed as by grinding or other machining operations. The finished product is then the arrangement shown in FIGS. 1 and 4.

It is to be understood that the invention is not limited to the specific embodiment herein illustrated and described, but may be used in other ways without departure from its spirit as defined by the following claims,

I claim:

1. In the manufacture of a double wall construction for a rocket, the steps of providing inner and outer concentric walls in spaced relation, weaving a thin, bendable wire in and out through pairs of substantially radially aligned holes in the walls and brazing the wire in the holes in the inner and outer walls.

2. A method of manufacture as in claim 1 wherein the portions of the wire externally of the walls are subsequently machined 01f.

References Cited in the file of this patent UNITED STATES PATENTS 2,286,909 Goddard June 16, 1942 2,544,422 Goddard Mar. 6, 1951 2,689,453 Goddard Sept. 21, 1954 2,693,026 Simpelaar Nov. 2, 1954 2,722,048 Gier Nov. 1, 1955 2,722,733 Meyer et al. Nov. 8, 1955 2,880,577 Halford et al Apr. 7, 1959 

1. IN THE MANUFACTURE OF A DOUBLE WALL CONSTRUCTION FOR A ROCKET, THE STEPS OF PROVIDING INNER AND OUTER CONCENTRIC WALLS IN SPACED RELATION, WEAVING A THIN, BENDABLE WIRE IN AND OUT THROUGH PAIRS OF SUBSTANTIALLY RADIALLY 